When the actress and nominee took to the stage at the Golden Globes on Sunday night to present alongside Reese Witherspoon, fans couldn't help but comment on the 49-year-old's face, with some Twitter users speculating that the Lion star had undergone multiple plastic surgery procedures.

"Nicole Kidman seems to have replaced her skin with plastic," one viewer wrote, while another said, "Do we think Nicole Kidman has had enough 'work' done yet? Yikes!" One commenter even wrote, "Nicole Kidman's wax figure looked so lifelike on the Golden Globes."

(Photo Credit: Getty Images)

Unfortunately for the mother-of-four, her Alexander McQueen silver gown didn't go over so well with critics either, landing her on a lot of worst-dressed lists.

The blonde beauty, who walked the red carpet alongside husband Keith Urban, has previously denied going under the knife. “To be honest, I am completely natural. I have nothing in my face or anything," she once said, later adding, "No surgery for me; I did try Botox, unfortunately, but I got out of it and now I can finally move my face again... I wear sunscreen, I don't smoke and I take care of myself, and I am proud to say that."

Nicole in 2007 vs. 2017. (Photo Credit: Getty Images)

Plastic surgery experts previously spoke toLife & Style about Nicole's transformation, outlining the procedures they believe she's had done based on comparisons of her face.

"The likely fillers around Nicole's mouth look very good," observed plastic surgeon Dr. Lyle Back, who has never worked with Nicole. He suspected the Aussie's tight jawline and smooth neck came courtesy of a mini-face-lift. Added Dr. Mirwat Sami, Botox seems to have smoothed Nicole's crow's-feet and the "11s between her brows... but her eyelids look heavy."